They found two compounds that met these criteria (calcium carbonate and calcium phosphate), added them to a common emollient to create a cream, and tested them under a variety of experimental conditions. For example, they applied the cream to samples of animal skin and to living animals, and tested it in the presence of artificial sweat (sweat is known to exacerbate the allergy, accelerating the release of nickel). Further, they conducted the tests with concentrations of nickel much higher than would be found in everyday situations.
"We were able to demonstrate that the particles could indeed capture nickel with high efficiency and prevent inflammation in nickel-sensitized animals," Karp says. Further, "we needed 11-fold less nanoparticles to get the same effect" as another common nickel-capture agent. (A significant drawback of the latter: it can penetrate the skin, and even small amounts can cause local and systemic toxicity.)
All results "suggest that nanoparticles can effectively prevent the penetration of nickel into the skin, and may therefore abrogate nickel-induced contact dermatitis," the team concluded in the Nature Nanotechnology paper.
|Contact: Holly Brown-Ayers|
Brigham and Women's Hospital